Field of the Invention
The present invention relates to an imprint apparatus, an imprint method, and a method of manufacturing an article.
Description of the Related Art
An imprint technique is a technique of forming a pattern to an imprint material on a substrate by using a mold. The imprint technique has received attention as one of lithography techniques of manufacturing magnetic storage media and semiconductor devices. An imprint apparatus using the imprint technique cures the imprint material (for example, an uncured photo-curable resin) on the substrate in a state in which the mold and the imprint material are in contact with each other. Then, the imprint apparatus widens the interval between the substrate and the mold, and releases the mold from the cured imprint material on the substrate, thereby forming the pattern of the imprint material on the substrate.
In the imprint apparatus, there is known a technique of deforming (curving) the pattern surface of the mold into a convex shape with respect to the substrate and bringing the mold into contact with the imprint material on the substrate in order to promote filling of the concave portion of the pattern of the mold with the imprint material. The concave portion of the pattern is easily filled with the imprint material by bringing the mold and the imprint material into contact with each other from the center to the outer periphery of the pattern surface of the mold. This makes it possible to reduce bubble residues.
It is important in the imprint apparatus to keep the thickness (residual layer thickness) of the imprint material constant when curing the imprint material so as to prevent the pattern formed on the substrate from being influenced by an etching process in a post-process. It is therefore necessary to bring the mold and the imprint material into contact with each other in a state in which the pattern surface of the mold and the substrate are maintained in parallel. Japanese Patent Laid-Open No. 2007-299994 has proposed a technique related to this. Japanese Patent Laid-Open No. 2007-299994 has disclosed a technique of obtaining three-dimensional flatness of the mold and the substrate and controlling, based on this flatness, the orientation of the substrate when bringing the mold and the imprint material into contact with each other.
In the conventional technique, however, no consideration is given to deformation in the mold and the substrate which is caused by a force (pressing force) generated when bringing the mold and the imprint material on the substrate into contact with each other. Therefore, only with control of the orientation of the substrate based on three-dimensional flatness of the mold and the substrate, a deviation may occur in parallelism between the mold and the substrate when actually bringing the mold and the imprint material on the substrate into contact with each other.